\smsubsection{Polling Location Related Analysis}
%\subsubsection{Polling Locations that Closed Late}
In the United States, poll closing hours vary from 6 P.M. to 9 P.M. depending on the
state~\cite{Info2007}. Some state statutes allow the voters waiting in
line at poll closing time to cast their ballots at the precinct, requiring those
polling locations to stay open late. If election officials knew which polling
places were likely to 
experience long lines they could deploy more equipment or personnel to
those locations. This analysis can assist them by providing
information about long lines that occurred in the current election, which they
could use to make predictions about where
long lines might occur in future elections.

This analysis gathers the time each machine was closed from the event log and
the precinct the machine was assigned to from the ballot image file
and generates a countywide chart detailing the number of polling
locations that stayed open after poll closing time and for how long. To handle
inaccurate machine date/time settings, our tool uses a time verification
algorithm described in Section 3.6 to exclude from our database any voting
machines whose time stamp is probably incorrect. 

